<?php

if (! defined ( 'BASEPATH' ))
	exit ( 'No direct script access allowed' );
/**
 * Code Igniter
 *
 * An open source application development framework for PHP 5.1.6 or newer
 *
 * @package		CodeIgniter
 * @author		ExpressionEngine Dev Team
 * @copyright	Copyright (c) 2008 - 2011, EllisLab, Inc.
 * @license		http://codeigniter.com/user_guide/license.html
 * @link		http://codeigniter.com
 * @since		Version 1.0
 * @filesource
 */

// ------------------------------------------------------------------------


/**
 * Database Utility Class
 *
 * @category	Database
 * @author		ExpressionEngine Dev Team
 * @link		http://codeigniter.com/user_guide/database/
 */
class CI_DB_utility extends CI_DB_forge {
	
	var $db;
	var $data_cache = array ();
	
	/**
	 * Constructor
	 *
	 * Grabs the CI super object instance so we can access it.
	 *
	 */
	function CI_DB_utility() {
		// Assign the main database object to $this->db
		$CI = & get_instance ();
		$this->db = & $CI->db;
		
		log_message ( 'debug', "Database Utility Class Initialized" );
	}
	
	// --------------------------------------------------------------------
	

	/**
	 * List databases
	 *
	 * @access	public
	 * @return	bool
	 */
	function list_databases() {
		// Is there a cached result?
		if (isset ( $this->data_cache ['db_names'] )) {
			return $this->data_cache ['db_names'];
		}
		
		$query = $this->db->query ( $this->_list_databases () );
		$dbs = array ();
		if ($query->num_rows () > 0) {
			foreach ( $query->result_array () as $row ) {
				$dbs [] = current ( $row );
			}
		}
		
		$this->data_cache ['db_names'] = $dbs;
		return $this->data_cache ['db_names'];
	}
	
	// --------------------------------------------------------------------
	

	/**
	 * Determine if a particular database exists
	 *
	 * @access	public
	 * @param	string
	 * @return	boolean
	 */
	function database_exists($database_name) {
		// Some databases won't have access to the list_databases() function, so
		// this is intended to allow them to override with their own functions as
		// defined in $driver_utility.php
		if (method_exists ( $this, '_database_exists' )) {
			return $this->_database_exists ( $database_name );
		} else {
			return (! in_array ( $database_name, $this->list_databases () )) ? FALSE : TRUE;
		}
	}
	
	// --------------------------------------------------------------------
	

	/**
	 * Optimize Table
	 *
	 * @access	public
	 * @param	string	the table name
	 * @return	bool
	 */
	function optimize_table($table_name) {
		$sql = $this->_optimize_table ( $table_name );
		
		if (is_bool ( $sql )) {
			show_error ( 'db_must_use_set' );
		}
		
		$query = $this->db->query ( $sql );
		$res = $query->result_array ();
		
		// Note: Due to a bug in current() that affects some versions
		// of PHP we can not pass function call directly into it
		return current ( $res );
	}
	
	// --------------------------------------------------------------------
	

	/**
	 * Optimize Database
	 *
	 * @access	public
	 * @return	array
	 */
	function optimize_database() {
		$result = array ();
		foreach ( $this->db->list_tables () as $table_name ) {
			$sql = $this->_optimize_table ( $table_name );
			
			if (is_bool ( $sql )) {
				return $sql;
			}
			
			$query = $this->db->query ( $sql );
			
			// Build the result array...
			// Note: Due to a bug in current() that affects some versions
			// of PHP we can not pass function call directly into it
			$res = $query->result_array ();
			$res = current ( $res );
			$key = str_replace ( $this->db->database . '.', '', current ( $res ) );
			$keys = array_keys ( $res );
			unset ( $res [$keys [0]] );
			
			$result [$key] = $res;
		}
		
		return $result;
	}
	
	// --------------------------------------------------------------------
	

	/**
	 * Repair Table
	 *
	 * @access	public
	 * @param	string	the table name
	 * @return	bool
	 */
	function repair_table($table_name) {
		$sql = $this->_repair_table ( $table_name );
		
		if (is_bool ( $sql )) {
			return $sql;
		}
		
		$query = $this->db->query ( $sql );
		
		// Note: Due to a bug in current() that affects some versions
		// of PHP we can not pass function call directly into it
		$res = $query->result_array ();
		return current ( $res );
	}
	
	// --------------------------------------------------------------------
	

	/**
	 * Generate CSV from a query result object
	 *
	 * @access	public
	 * @param	object	The query result object
	 * @param	string	The delimiter - comma by default
	 * @param	string	The newline character - \n by default
	 * @param	string	The enclosure - double quote by default
	 * @return	string
	 */
	function csv_from_result($query, $delim = ",", $newline = "\n", $enclosure = '"') {
		if (! is_object ( $query ) or ! method_exists ( $query, 'list_fields' )) {
			show_error ( 'You must submit a valid result object' );
		}
		
		$out = '';
		
		// First generate the headings from the table column names
		foreach ( $query->list_fields () as $name ) {
			$out .= $enclosure . str_replace ( $enclosure, $enclosure . $enclosure, $name ) . $enclosure . $delim;
		}
		
		$out = rtrim ( $out );
		$out .= $newline;
		
		// Next blast through the result array and build out the rows
		foreach ( $query->result_array () as $row ) {
			foreach ( $row as $item ) {
				$out .= $enclosure . str_replace ( $enclosure, $enclosure . $enclosure, $item ) . $enclosure . $delim;
			}
			$out = rtrim ( $out );
			$out .= $newline;
		}
		
		return $out;
	}
	
	// --------------------------------------------------------------------
	

	/**
	 * Generate XML data from a query result object
	 *
	 * @access	public
	 * @param	object	The query result object
	 * @param	array	Any preferences
	 * @return	string
	 */
	function xml_from_result($query, $params = array()) {
		if (! is_object ( $query ) or ! method_exists ( $query, 'list_fields' )) {
			show_error ( 'You must submit a valid result object' );
		}
		
		// Set our default values
		foreach ( array ('root' => 'root', 'element' => 'element', 'newline' => "\n", 'tab' => "\t" ) as $key => $val ) {
			if (! isset ( $params [$key] )) {
				$params [$key] = $val;
			}
		}
		
		// Create variables for convenience
		extract ( $params );
		
		// Load the xml helper
		$CI = & get_instance ();
		$CI->load->helper ( 'xml' );
		
		// Generate the result
		$xml = "<{$root}>" . $newline;
		foreach ( $query->result_array () as $row ) {
			$xml .= $tab . "<{$element}>" . $newline;
			
			foreach ( $row as $key => $val ) {
				$xml .= $tab . $tab . "<{$key}>" . xml_convert ( $val ) . "</{$key}>" . $newline;
			}
			$xml .= $tab . "</{$element}>" . $newline;
		}
		$xml .= "</$root>" . $newline;
		
		return $xml;
	}
	
	// --------------------------------------------------------------------
	

	/**
	 * Database Backup
	 *
	 * @access	public
	 * @return	void
	 */
	function backup($params = array()) {
		// If the parameters have not been submitted as an
		// array then we know that it is simply the table
		// name, which is a valid short cut.
		if (is_string ( $params )) {
			$params = array ('tables' => $params );
		}
		
		// ------------------------------------------------------
		

		// Set up our default preferences
		$prefs = array ('tables' => array (), 'ignore' => array (), 'filename' => '', 'format' => 'gzip', // gzip, zip, txt
'add_drop' => TRUE, 'add_insert' => TRUE, 'newline' => "\n" );
		
		// Did the user submit any preferences? If so set them....
		if (count ( $params ) > 0) {
			foreach ( $prefs as $key => $val ) {
				if (isset ( $params [$key] )) {
					$prefs [$key] = $params [$key];
				}
			}
		}
		
		// ------------------------------------------------------
		

		// Are we backing up a complete database or individual tables?
		// If no table names were submitted we'll fetch the entire table list
		if (count ( $prefs ['tables'] ) == 0) {
			$prefs ['tables'] = $this->db->list_tables ();
		}
		
		// ------------------------------------------------------
		

		// Validate the format
		if (! in_array ( $prefs ['format'], array ('gzip', 'zip', 'txt' ), TRUE )) {
			$prefs ['format'] = 'txt';
		}
		
		// ------------------------------------------------------
		

		// Is the encoder supported?  If not, we'll either issue an
		// error or use plain text depending on the debug settings
		if (($prefs ['format'] == 'gzip' and ! @function_exists ( 'gzencode' )) or ($prefs ['format'] == 'zip' and ! @function_exists ( 'gzcompress' ))) {
			if ($this->db->db_debug) {
				return $this->db->display_error ( 'db_unsuported_compression' );
			}
			
			$prefs ['format'] = 'txt';
		}
		
		// ------------------------------------------------------
		

		// Set the filename if not provided - Only needed with Zip files
		if ($prefs ['filename'] == '' and $prefs ['format'] == 'zip') {
			$prefs ['filename'] = (count ( $prefs ['tables'] ) == 1) ? $prefs ['tables'] : $this->db->database;
			$prefs ['filename'] .= '_' . date ( 'Y-m-d_H-i', time () );
		}
		
		// ------------------------------------------------------
		

		// Was a Gzip file requested?
		if ($prefs ['format'] == 'gzip') {
			return gzencode ( $this->_backup ( $prefs ) );
		}
		
		// ------------------------------------------------------
		

		// Was a text file requested?
		if ($prefs ['format'] == 'txt') {
			return $this->_backup ( $prefs );
		}
		
		// ------------------------------------------------------
		

		// Was a Zip file requested?
		if ($prefs ['format'] == 'zip') {
			// If they included the .zip file extension we'll remove it
			if (preg_match ( "|.+?\.zip$|", $prefs ['filename'] )) {
				$prefs ['filename'] = str_replace ( '.zip', '', $prefs ['filename'] );
			}
			
			// Tack on the ".sql" file extension if needed
			if (! preg_match ( "|.+?\.sql$|", $prefs ['filename'] )) {
				$prefs ['filename'] .= '.sql';
			}
			
			// Load the Zip class and output it
			

			$CI = & get_instance ();
			$CI->load->library ( 'zip' );
			$CI->zip->add_data ( $prefs ['filename'], $this->_backup ( $prefs ) );
			return $CI->zip->get_zip ();
		}
	
	}

}


/* End of file DB_utility.php */
/* Location: ./system/database/DB_utility.php */